Method and device for identifying and localizing a fire

ABSTRACT

The invention relates to a method and a device for detecting and localizing sources of fire in one or more monitored areas (R 1 , . . . , R n ) utilizing a suction pipe system ( 3 ) connecting the plurality of monitored areas (R 1 , . . . , R n ) and which communicates with each individual monitored area (R 1 , . . . , R n ) by means of at least one suction opening ( 4 ), a suction device ( 5 ) for extracting air samples ( 6 ) representative of the room air of the individual monitored areas (R 1 , . . . , R n ) from the individual monitored areas (R 1 , . . . , R n ) by means of the suction pipe system (3) and the suction openings ( 4 ), and a sensor ( 7 ) for detecting at least one fire parameter in the air samples ( 6 ) extracted through the suction pipe system ( 3 ), whereby the inventive device comprises a blowing device ( 8 ) for blowing out the air samples ( 6 ) suctioned into the suction pipe system ( 3 ) when sensor ( 7 ) detects at least one fire parameter in the extracted air samples ( 6 ). The fire is localized by means of the transit time measurement of a re-extracted fire parameter.

The invention relates to a method for detecting and localizing a fireand/or the origin of a fire in one or more monitored areas as well as adevice for realizing the method.

The invention starts out from a fire detecting device having a sensorfor detecting a fire parameter which is fed a representative volume ofroom or device air through a suction pipe system by means of a suctiondevice such as a fan.

The term “fire parameter” is to be understood as physical variableswhich are subject to measurable changes in the vicinity of an incipientfire, e.g. ambient temperature, solid or liquid or gaseous content inthe ambient air (accumulation of smoke particles or particulate matteror accumulating smoke or gases) or local background radiation.

Both procedures as well as fire detecting devices of the cited type areknown and serve for prompt detecting of fires still in their incipientphase. Typical areas of application are either rooms containinghigh-quality or important equipment such as, for example, roomscontaining computer systems in banks or the like, or even just thecomputer equipment itself. To this end, representative samples of theroom air or the device cooling air are continually extracted, referredto in the following as “air sample.” An appropriate means for extractingsuch air samples and feeding same to the fire sensor, to the housing ofthe fire sensor respectively, is a suction pipe system designed as asystem of conduits which are mounted, for example, below the ceiling ofthe room and lead to air intake openings in the housing of the firesensor and which sucks the air samples in through air suction openingsprovided in the suction pipe system. An important premise in detectingan incipient fire at its earliest stage is that the fire detectingdevice continually extracts a sufficiently representative amount of airwithout interruption to supply the sensor sensing chamber. An applicablesensor here would be, for example, a point-based smoke sensor whichmeasures the light turbidity in a sensor smoke chamber caused byparticulate matter, or also a scattered light sensor integrated in theintake path which detects scattered light caused by smoke particles at acenter of the sensor.

Methods and devices using a plurality of suction pipe systems to detectand localize sources of fire in one or more monitored areas are knownfrom the prior art and have been developed based on the fact that, forexample, it is very difficult for firefighting crews to localize thesource of a fire in large halls, office buildings, hotels or ships. Onesingle smoke suction system having a single fire-detecting unitmay—subject to national regulations—monitor an area of up to 2000 m²,which may also comprise several rooms. In order to enable an operativealarm site to be quickly localized, requirements have been defined suchas those set forth, for example, in Germany's “Guidelines for AutomaticFire Reporting Installations, Planning and Construction” (VdS 2095).Pursuant thereto, a plurality of rooms may only be grouped together intoone alarm area when the rooms are adjacent, the access to same can bereadily seen at a glance, the total surface area does not exceed 1000m², and there are clear visual alarm indicators at the fire alarmmonitoring station which, in the event of a fire alarm, indicate thearea where the fire is located.

While devices for detecting fire which operate on an aspirativeprinciple, in which a plurality of areas to be monitored are connectedby one individual smoke suction system, offer the advantage of theearliest possible detection of fire, there is no guarantee that the siteof the fire can be localized in such a commonly-shared smoke suctionsystem monitoring a plurality of areas. This is due to the fact that theindividual air samples, each representing the room air from oneindividual monitored area, are fed to the sensor for detecting a fireparameter after having been mixed together in the jointly-shared suctionpipe system. All the sensor can thus establish is that a fire broke outand/or is imminent in one of the areas being monitored. In order to beable to additionally ensure a localization of the seat of the fire inone of said monitored areas, it is usually necessary to feed each airsample extracted from each individual monitored area to another sensorof a separate suction pipe system in order to detect a fire parameter.Yet when monitoring a plurality of monitored areas, this has as thedisadvantage that the corresponding number of suction pipe systems mustbe in place, which involves a very complex implementation of the one ormore aspirative fire detection system(s) both structurally as well asfinancially.

FR 2670010 Al discloses alarm boxes which serve to identify thesmoke-sucking joint in a branched suction pipe system. These alarm boxesconsist of a point-based smoke sensor built into a housing with a cablethreading to connect the inlet and outlet pipes and a signal light onits cover. Yet disadvantageous to this construction is that because oftheir size, design and price, these alarm boxes cannot be employed ateach individual air intake opening.

Known further from WO 00/68909 is a method and a device for detectingfires in monitored areas by means of which the source of a fire can belocalized. This method utilizes an appropriate device in each monitoredarea comprised of two crossing pipes, into which one or more fanscontinually suck in air from the monitored areas through suctionopenings disposed in the pipes and feed same to at least one sensor fordetecting one fire parameter per pipe. The localization of the seat ofthe fire thereby follows from the responding of the two sensorsallocated to the crossing pipes. A plurality of areas is monitored bysuch pipes arranged as a matrix of columns and rows, where appropriateby one cumulative sensor each for the column and row arrangement. Adisadvantage to this known device, however, is the very substantialinstallation outlay for the matrix-like system of pipes.

Known from the German DE 3 237 021 C2 patent specification is aselective gas/smoke detection system having a plurality of suction linesconnected separately to various measuring points in an area to bemonitored in order to withdraw samples of air or gas at said measuringpoints. Here, a gas or smoke sensor connected to these lines reacts tothe presence of a specific gas in the sample upon a fixed thresholdbeing exceeded and emits a detection signal which controls an indicatorand/or alarm circuit. Shut-off valves which are cyclically andperiodically energized in a controlled loop are furthermore arranged onthe individual suction lines. Detecting fire with this gas/smokedetection system ensues in that in the absence of a detection signal,the control unit sets the shut-off valves such that all the suctionlines are simultaneously in open connection with the sensor, and upon adetection signal being received, switches them over to a sensing mode inwhich the suction lines are conventionally brought into open connectionwith the sensor consecutively or in groups. This function for detectingthe origin of fire presupposes, however, that the sensor can be broughtinto connection with each area to be monitored by way of individual andselectively-opened feed lines. This inherently means having to installan extensive system of pipes in order to create these individuallyselectable connections. Likewise disadvantageous is the high cost ofinstalling the necessary suction lines.

WO 93/23736 further makes known an air pollution/smoke detection devicebased on a network-like configured suction system having a large numberof sampling sites at which gas is extracted from each room to bemonitored. This pollution/smoke detection device has a plurality ofinlet ports connected to the grid-like suction system and monitoredindividually. Under normal circumstances, all these inlets remain openuntil the detection device detects pollution/smoke. Selectively closingthe inlet ports then allows the localizing and detecting of a fire zone.But the operation of this detection device also requires an extensiveinstallation of suction lines to form a grid-like structure in order toensure reliable detection of a fire source. Here as well, thedisadvantage to this known device lies in the high installation outlayfor the system of pipes.

Further known from DE 101 25 687 Al is a device for detecting andlocalizing a source of fire in one or more monitored areas. The devicecomprises a main sensor for detecting a fire parameter with an intakeunit continuously feeding samples of the ambient air from the monitoredareas through a line disposed with intake ports arranged in eachmonitoring chamber. One sub-sensor each is thereby provided on or in thevicinity of at least one suction opening per monitored area, which isswitched on by a switch-on signal transmitted by a controller inaccordance with a detection signal emitted by the main sensor. Theswitched-on sub-sensor thereby serves in the detecting of the source ofthe fire and thus for localizing the fire source from the plurality ofmonitored areas. This device known from the prior art has thedisadvantage that due to the number of sub-sensors employed, the costsassociated with the fire detecting device are relatively high andfurthermore necessitates a relatively complex wiring of the sub-sensorswhen installing the device.

One task addressed by the present invention is to provide a simple andeconomical device and a method for detecting sources of fire whichcombines the advantages of known smoke and gas suction systems—activeintake and concealed mounting—with the advantage of localizing eachindividual suction opening and thus detecting an actual seat of fire oractual gaseous impurity as occurs when a fire develops. A further taskaddressed by the present invention consists of providing afire-extinguishing system comprising an aspirative fire detection devicewhich affords both reliable fire detection as well as localization ofthe site of a fire from a plurality of monitored areas, whereby the firedetection device can dispense with the need for a plurality of suctionpipe systems connecting the individual monitored areas to one sensor inorder to detect a fire parameter.

According to the invention, this task is solved by a method of the typedescribed at the outset having the following procedural steps: airsamples representative of each individual monitored area are extractedfrom said individual monitored areas—preferably continuously—through acommon suction pipe system; at least one fire parameter is establishedfor the air samples sucked in through the suction pipe system by the atleast one sensor provided for detecting fire parameters; the suctionedair samples within the suction pipe system are blown out by means of ablower or suction/blower device; representative air samples of the roomair from each of the individual monitored areas are re-extracted throughthe suction pipe system for as long as necessary until the at least onesensor re-detects a fire parameter in the air samples; the time elapsedbefore the re-detecting of the fire parameter in the previouslyre-extracted air samples is evaluated in order to localize an actualfire or the site of an imminent fire from one of the many monitoredareas; and a signal is emitted which indicates the development and/orpresence of a fire in one or more of the monitored areas, wherein thesignal also contains further information for a precise localization ofthe fire in the one or more monitored areas.

The underlying technical problem of the present invention is furthersolved by a device comprising a suction pipe system connecting theplurality of areas to be monitored which communicates with eachindividual monitored area by means of at least one suction opening, asuction device to extract representative air samples from the individualmonitored areas by means of the suction pipe system and the suctionopenings, and at least one sensor for detecting at least One fireparameter in the air samples extracted through the suction pipe system,whereby the device is characterized by a blowing device for blowing outthe air samples sucked into the suction pipe system when the at leastone sensor detects at least one fire parameter in the extracted airsamples, and by at least one indicator element which identifies the siteof a fire in one of the monitored areas and/or by a communication devicewhich transmits information on the development and/or presence of a firein one or more of the monitored areas and on the precise location of thefire in the one or more monitored areas to a location remote of thedevice.

The task of applying the technique is solved by utilizing a device inaccordance with the invention as a fire detection component of a fireextinguishing system for activating the introduction of a fireextinguishing agent in one of the monitored areas.

An essential aspect of the present invention relates to the fact thatbased on the already widespread use of installations for smoke or gassuction systems—also known as aspirative monitoring systems—the onlytechnical approach that makes sense is a simple and economicalretrofitting to achieve individual detection of fire sources or gasimpurities under the criteria of existing norms. At the same time, asituation where the associated retrofitting runs into substantialconstruction and operating costs in order to meet desired safetystandards must be avoided. The particular advantages of the inventionare seen in that not only are the requirements of detecting andlocalizing a fire and/or the onset of a fire in one of a plurality ofmonitored areas attainable following simple retrofitting of existingaspirative systems together with concurrent low operating costsutilizing a very easy to realize and thereby very effective method, butthe inventive method's localizing of the site of a fire also opens upnew applications for smoke suction systems. This thus dispenses with theneed for, as an example, a plurality of point-based fire alarms as usedto date in buildings having a plurality of individual rooms. Theinventive method affords the reliable detection of a fire or the onsetof a fire in a monitored area and for this monitored area to belocalized from a plurality of monitored areas through the use of justone suction pipe system, one sensor to detect a fire parameter, and onesuction/blowing device. Doing so does away with the need for anelaborate installation of a plurality of suction pipe systems incombination with a plurality of sensors, which clearly andadvantageously reduces the structural complexity of the installation orthe retrofitting of a plurality of monitoring areas with such a firedetection device. Because the fire detection and localization isaspiratively based, the present method is extremely sensitive and inparticular independent of spatial heights or high air speeds within theindividual monitored areas. High ceilings or higher air speeds lead, forexample in air-conditioned areas, to a vigorous diluting of smoke. Thehigh detection sensitivity of the inventive fire detection andlocalization method is to a large extent independent of theseparameters. The inventive method moreover offers the advantage that afire and/or the onset of a fire can be reliably identified and locatedindependent of disturbances such as dust, dirt, humidity or extremetemperatures in the individual monitored areas. The method according toinvention also makes possible the use of only one single suction pipesystem which can be integrated virtually invisibly into the building'sarchitecture so that aesthetic interests can be commensurately takeninto full account.

Blowing out the air samples sucked into and present within the suctionpipe system after the sensor for detecting fire parameters detects atleast one fire parameter in the air sample sucked through the suctionpipe system occasions fresh air to then fill the entire suction pipesystem; i.e., air which definitely no longer exhibits any fireparameter. Following the air samples being blown out, the suction pipesystem re-extracts air samples representative of the room air of eachindividual monitored area from the individual monitored areas. Anessential aspect of the method according to the invention is now themeasuring of the transit time and/or specific transit time values untilthe sensor once again detects a fire parameter in the air samples suckedthrough the commonly-shared suction pipe system. This transit time issubsequently evaluated in order to localize the site of the fire or thesite where a fire is developing, based on the fact that each individualmonitored area is at a certain distance from the sensor and alsoexhibits a transit time dependent on the suction pipe system.

In realizing the above-described method, the device according to theinvention allows for providing a suction device to extractrepresentative air samples of the room air within the individualmonitored areas from each individual monitored area through the suctionpipe system communicating with each individual monitored area viasuction openings, and subsequently feed same to the sensor. Of course,to lower the probability of sensor failure, a plurality of sensors canalso be used for detecting a fire parameter with the device according tothe invention. It would also be conceivable to use one sensor for onespecific fire parameter and another sensor for another fire parameter.The device in accordance with the invention is particularly advantageousin terms of maintenance and service. Utilizing only one sensor, onesuction device and one blowing device, which can be arranged in aseparate area external the monitored areas and thus readily accessibleto maintenance personnel, not only clearly reduces overall maintenancecosts, but also the maintenance and service personnel do not need toenter the monitored areas, which is a particularly important aspect inthe case of cleanrooms, ship cabins or prison cells. In a particularlypreferred embodiment, the device according to the invention additionallyexhibits a communication device, by means of which information istransmitted to a site remote of the device regarding the emergenceand/or presence of a fire in one or more of the monitored areas andregarding the precise location of the fire in the one or more monitoredareas. A site remote of the device in this context can be for example afire alarm monitoring station or a control center for task force crews.The communication device thereby enables for example either a wired orwireless transmission of a corresponding signal containing the relevantinformation in the event of a fire to an associated receiver. Saidcommunication device can itself be controllable, of course, for instancein order to change or test an operational state of the device. IRtechnology would also be applicable as a conceivable communicationmedium.

Preferred embodiments of the invention related to the method areindicated in subclaims 2 to 9 and related to the device in subclaims 11to 20.

For instance, it is particularly preferred in terms of the method forthe flow rate of an air sample in the suction pipe system to bedetermined as the respective air samples are being withdrawn from theindividual monitored areas. This flow rate then serves in calculatingthe time necessary to fully blow out the air samples located in thesuction pipe system. The determination or measurement of the flow ratecan thereby be done either directly or indirectly; i.e., for examplebased on device parameters such as the output of the suction device, theeffective flow cross-section of the suction pipe system and therespective diameters to the suction openings disposed along the suctionpipe system. A direct measurement is possible with a plurality ofdifferent flow rate-measuring methods known in the art. It would beconceivable here to make use of, for example, hot-wire or hot-filmanemometry. Calculating the time necessary for the blowing device tofully blow the air samples out through the suction pipe system canadvantageously realize a minimizing of the blow-out time and localizesthe site of the fire in the shortest possible time.

A particularly advantageous realization of the inventive method providesfor the process step of blowing out the extracted air samples present inthe suction pipe system to further comprise the process step ofdetermining the flow rate during this blowing out in order to calculatethe time necessary to fully blow the air samples out of the suction pipesystem. Here, note is made of the fact that suctioning and blowing outvery probably take place at different flow rates, even if the same fanis used for both suctioning and blowing, since fans normally exhibitdifferent characteristic curves for these two modes of operation. Basedon the flow rate determined during the blowing out, the time which isnecessary to fully blow all the air samples out of the suction pipesystem is then calculated, whereby this calculated time is a very exactvalue.

It is furthermore particularly preferred to determine the flow rate ofthe air samples in the suction pipe system during the renewed extractionof the respective air samples from the individual monitored areas. Thedetermined flow rate thereafter serves as the basis for calculating thetransit time of the respective air samples representative of the roomair of the individual monitored areas during the renewed extraction ofthe respective air samples from the individual monitored areas. Thisembodiment of the method achieves a particularly high reliability andaccuracy to the localization of the site of the fire. Of course, transittime occurring with the renewed extraction of the respective air samplesfrom the individual monitored areas can also be calculated on the basisof, for example, the flow rate determined during the continuousextraction of the respective air samples from the individual monitoredareas or on the basis of theoretical values.

Air sampling according to the inventive method is realized by means of asuction device, whereby the subsequent re-extraction of air samples fromthe individual monitored areas ensues with a suction line which isreduced in comparison to the suction line used for the previouslyperformed air sample extraction. In particularly preferred manner, thisthus achieves a longer transit time for the re-suctioning and thedifference in transit times between the different suction openings alsoincreases. As a result, a more reliable correlating of measured transittime to specific monitored area is attained. Allowing for a transit timemeasurement tolerance of, for example, 0.5 to 2 seconds would beconceivable. In order to avoid,two neighboring suction openingsoverlapping in transit time tolerance ranges, which would result inlocalization of a fire no longer being possible, the re-extraction istherefore run at a lower suction line. Thus, this embodimentadvantageously increases the accuracy of the transit time measurement.Yet it is, of course, also conceivable—additionally or in place of—toincrease the sampling rate for the fire parameter in the sensor duringre-suctioning, which likewise increases the accuracy of the transit timemeasurement.

A particularly preferred realization of the method according to theinvention further provides for an auto-adjusting procedure, comprisingthe following process steps: a fire parameter is artificially producedat a suction opening at the most distant monitored area from the atleast one sensor over the entire time of the auto-adjusting procedure;air samples are suctioned from the individual monitored areas throughthe commonly-shared suction pipe system until the at least one sensordetects the artificially-generated fire parameter in the extracted airsamples; the extracted air samples located within the suction pipesystem are blown out by means of a blowing or suctioning/blowing device;new air samples are again suctioned out of the individual monitoredareas through the suction pipe system at least until the at least onesensor re-detects an artificially-generated fire parameter in the airsamples; the transit time elapsed until the re-detection of theartificially-generated fire parameter of the re-extracted air samples isevaluated in order to determine the maximum transit time for the suctionpipe system; the transit times for the respective air samplesrepresentative of the room air of the individual monitored areas arecalculated based on the previously-determined maximum transit times andthe configuration of the suction pipe system, in particular the distancebetween the suction openings, the diameter to the suction pipe systemand the diameter of the suction openings; and the calculated transittimes for the respective air samples are stored in a table. Theadvantage to this embodiment, using the auto-adjusting procedure, isparticularly based on no longer needing to measure the flow rate of theair samples in the suction pipe system. In this regard, it is providedto put the fire detection device into operation in a self-learning mode,generate smoke at the most distant suction opening, and to measure thetransit time with the process steps of suctioning, blowing out andre-suctioning. Based on the maximum transit time and the specific pipeconfiguration, the transit times for all suction openings can then becalculated. This calculation can be performed by the fire detectiondevice itself or externally, for example on a laptop computer. Thecalculated fire detection device transit times are then subsequentlystored to a table.

A particularly preferred embodiment of the method according to theinvention making use of the auto-adjusting procedure further providesfor utilizing a correcting function on the calculated transit timesstored in the table in order to update the transit time values occurringfor the individual monitored areas. Doing so takes into account that thesuction pipe system and/or the suction openings may gradually get dirtyover time, which would go hand in hand with a gradual change in the flowrate. A correcting function can thus be used to calculate currenttransit times from the transit times stored in the table.

Evaluating the transit times in the inventive method prior to therenewed detecting of fire parameters for the re-extracted air samplespreferably ensues by comparing the resulting transit time withrespective transit times computed theoretically for the individualmonitored areas. Conceivable as applicable parameters on which thetheoretically-calculated transit times can depend include the length ofthe respective sections of the suction pipe system between the sensorand the suction openings of the respective monitored areas, theeffective flow cross-section of the suction pipe system and/or therespective sections of the suction pipe system between the sensor andthe suction openings of the respective monitored areas, and the flowrate of the air samples in the suction pipe system and/or in therespective sections of the suction pipe system between the sensor andthe suction openings of the respectively monitored areas. However, otherparameters on which the theoretically-calculated transit time can dependare, of course, also conceivable.

One advantageous embodiment to the inventive device is provided by thedevice additionally exhibiting a controller to enable a time-coordinatedcontrolling of the suction device and the blowing device in agreementwith a signal emitted by the at least one sensor when the sensor detectsat least one fire parameter in the air samples.

Said controller is preferably configured such that the suction device isfirst set to effect a continuous withdrawal of air samplesrepresentative of the room air from the individual monitored areasthrough the common suction pipe system. Should the sensor then detect atleast one fire parameter in the extracted air samples, and thus send thecorresponding signal to the controller, the controller sends acorresponding signal to the suction device in response thereto in orderto shut off same, whereby at the same time or directly thereafter, afurther signal is issued by the controller to the blowing device toswitch on said blowing device in order to blow out the extracted airsamples located within:the suction pipe system. In accordance with theinvention, it is thereby provided for the controller to send anothersignal to the blowing device after a fixed time in order to shut if off,whereby at the same time or directly thereafter, a signal issues fromthe controller to the suction device in order to effect a renewedcontinuous extraction of air samples representative of the room air ofthe individual monitored areas from the individual monitored areasthrough the suction pipe system. The fixed time during which the blowingdevice is active is either a time determined theoretically on the basisof device parameters and stored in a memory, or is a time determined bymeans of a measured flow rate value to an air sample in the suction pipesystem during the continues extraction of the respective air samplesfrom the individual monitored areas.

A particularly preferred embodiment of the inventive device furtherprovides for a memory device in which transit time values can be stored.The values saved in this memory can be, for example, transit timesdetermined during an auto-adjusting procedure based on a maximum transittime and the pipe configuration.

Particularly preferred is for the device according to invention toexhibit at least one smoke generator arranged near a suction opening andwhich can artificially generate a fire parameter for the purpose ofsetting and testing the fire detection device. It is thus possible whenputting the fire detection device into operation to set it in aself-learning mode to measure the smoke generated by means of the smokegenerator at the most distant suction opening and the transit time ofthe artificially-generated smoke, the artificially-generated fireparameter respectively. This thus enables the measuring of a maximumtransit time, based on which and given knowledge of the pipeconfiguration, the transit times for all suction openings can becalculated. It is, of course, also conceivable here for the firegenerator to be arranged at another suction opening, respectively aplurality of smoke generators provided at different suction openings.

In one possible realization, the device according to the inventionfurther comprises a sensor for measuring the flow rate of the airsamples in the suction pipe system. In so doing, it is advantageouslypossible to determine the flow rate of the extracted air samples in thesuction pipe system, in order to calculate based on same the timenecessary for the blowing device to completely blow out the air samplespresent in the suction pipe system. The flow rate determined with thehelp of the sensor can moreover serve in calculating the transit timesof the respective air samples representative of the air room of theindividual monitored areas during the re-extraction of the respectiveair samples from said individual monitored areas. Examples of sensorsfor measuring the flow rate are known in the prior art and includesensors based on the principle of hot film and/or hot wire anemometry.It would furthermore be conceivable to determine the flow rate based ontheoretical device parameters instead of measuring the flow rate with asensor. Likewise conceivable here would also be only switching on thesensor to measure the flow rate for the duration of one self-learningmode upon device start-up.

Particularly preferred is to provide a processor for evaluating a signalemitted by the at least one sensor when the sensor detects a fireparameter in an air sample and a control signal emitted by thecontroller to the suction device and/or blowing device. The processor isthereby advantageously configured such that it determines the transittime of the air sample representative of the respective room air of theindividual monitored areas by the renewed continuous extraction fromeach individual monitored area through the suction pipe system based onthe signal, in order to thus localize the site of the fire or thedeveloping fire. Evaluating the resulting transit time is therebyperformed in the processor by comparing the resultant transit time withrespective transit times computed theoretically for the individualmonitoring areas. The theoretically-computed transit times can bedependent on, for example, the length of the respective sections of thesuction pipe system between the sensor and the respective monitoredareas, the effective flow cross-section of the suction pipe systemand/or the respective sections of the suction pipe system between thesensor and the respective monitored areas, and the flow rate to the airsample in the suction pipe system and/or in the respective sections ofthe suction pipe system between the sensor and the suction openings ofthe respective monitored area. By analyzing the transit times,localizing the site of the fire becomes possible.

An advantageous embodiment of the inventive device provides for thediameters and/or the cross-sectional shape to the individual suctionopenings to be configured contingent upon the respectively monitoredareas.

Conceivable here in terms of the monitored areas which are disposedfarther from the suction/blowing device would be to utilize suctionopenings with larger cross-sections than the monitored areas which arecloser to the suction/blowing device. The respective distance of themonitored areas from the suction/blowing device is defined by thedistance an air sample must traverse the suction pipe system from therespective suction opening in the respective monitored area to thesuction device. The respective cross-sectional shape or cross-sectionalsize to the individual suction openings are designed in such a way thatthey take the drop in pressure occurring in the suction pipe system intoaccount. The inventive embodiment to the suction openings therebyenables the inventive device to be equally sensitive in terms of firedetection and fire localization for each of the plurality of monitoredareas. In one possible realization, the individual suction openings inthe suction pipe system could be adapted to given conditions followinginstallation of the pipe system in the building. It would beconceivable, for example, to initially configure all suction openings tobe the same size, having the same cross-sectional shape respectively,whereby the respective suction openings are defined post-installation byaffixing a corresponding diaphragm aperture to the suction openings.Applicable here would be, for example, a perforated film or perforatedclip, whereby the hole size in the film or the clip is adapted to thegiven spatial circumstances. Of course other embodiments are just asconceivable. Also possible would be for the suction pipe system to beconfigured such that the cross-sectional shape to the suction pipesystem will vary according to installation conditions.

A particularly advantageous realization provides for configuring thesuction device and the blowing device together as one blower. Saidblower is thus designed such that it changes the direction it conveysair in response to the control signal from the controller. This thusallows achieving a further reduction in the number of componentscomprising the inventive device, which in turn advantageously lowers thecosts of manufacturing the device in accordance with the invention.

In order to further reduce the number of components comprising the firedetection and fire localization device according to invention, thesuction device and the blowing device are advantageously configuredtogether as one blower, whereby said blower is one affording reversal ofrotation.

A further realization of the device according to invention in which thesuction device and the blowing device are configured together as oneblower provides for the blower to be a fan having the appropriateventilation flaps so as to change the direction it conveys air. Otherembodiments are of course also conceivable here.

As indicated above, the inventive device comprises indicator elementswhich identify the site of a fire in one of the monitored areas. Theseindicator elements can be in the proximity of the entrances to theseareas or in the proximity of the fire detection device respectively. Thecommunication means or one input component for the connection to acommunication bus with a fire alarm central station serves to forwardinformation on the site of a fire to the central station, in order todisplay it, for example, in plain text on the control panel (e.g. “firein Area X”). Additionally to or in place of the indicator elements, theinventive device can further comprise a communication device whichtransmits information regarding the onset and/or presence of a fire inone or more of the monitored areas and regarding the precise location ofthe fire in the one or more monitored areas to a site remote of thedevice, such as, for example, to a fire alarm central station or acontrol center for task force crews. Depending upon application, thecommunication device thereby preferably affords either the wired orwireless possibility of emitting an appropriate signal to at least oneassociated receiver disposed at a distance from the inventive devicewhen the need arises. Said communication device can, of course, alsoitself be externally controllable, for instance in order to change ortest an operational state of the device. IR technology would also beapplicable as a conceivable communication medium.

The following will make reference to the drawings in describing apreferred embodiment of the inventive device in greater detail.

Shown are:

FIG. 1 a schematic representation of an embodiment of the inventivedevice for detecting a fire and localizing the fire in one monitoredarea out of a plurality of monitored areas; and

FIG. 2 a, b graphic representations of the signal dynamics.

FIG. 1 is a schematic representation of a preferred embodiment of theinventive device for detecting a fire and for localizing the fire withinone monitored area (R₁, R₂, . . . , R_(n)) from a plurality of monitoredareas (R₁, R₂, . . . , R_(n)). The inventive device according to FIG. 1involves a centrally-arranged, aspirating fire detection device able toprecisely localize the site of a fire. In the embodiment as depicted,the device is used to monitor four separate monitored areas (R₁, R₂, R₃,R₄). It is hereby provided for each one air sample (6), representativeof the room air of the respective monitored areas (R₁, . . . , R₄) to becontinuously extracted from the respective monitored areas (R₁, . . . ,R₄) through a common suction pipe system (3). To this end, a suctiondevice (5) configured as a blower is provided at one end of the suctionpipe system (3). The air samples (6) extracted through the commonsuction pipe system (3) by the suction device (5) are conveyed to asensor or a plurality of sensors (7) to detect one or more fireparameters. It would be conceivable in this regard to arrange thesuction device (5) together with the sensor (7) in one common housing(2).

Sensor (7) serves to analyze the air samples (6), each representative ofthe room air of the monitored areas (R₁, . . . , R₄) to be monitored, assuctioned through the suction pipe system (3) for a fire parameter.Applicable as sensor (7) would be any of the devices known in the priorart. In the event of a fire breaking out in one of monitored areas (R₁,. . . , R₄) or the room air of a monitored area (R₁, . . . , R₄)containing fire parameters and sensor (7) detects said fire parametersin the extracted air samples (6), same emits the corresponding signal toa controller (9).

In response to this signal, controller (9) emits the appropriate controlsignal to suction device (5) so as to switch it off. At the same time orimmediately thereafter, a further signal is emitted by controller (9) toa blowing device to activate same. Said blowing device (8) isadvantageously arranged such that when in operation, it blows out theair samples (6) already extracted and still present in the suction pipesystem (3). In particularly advantageous fashion in the embodiment asdepicted, the suction device (5) and the blowing device (8) areconfigured together as one blower (11) which changes its air-conveyingdirection in response to a signal emitted by controller (9). As anexample, the blower could be a reversing-rotation fan, yet alsoconceivable would be a blower (11) having a fan with ventilation flaps.When blowing out the suction pipe system, blowing device (8) brings infresh air, i.e. outside air, toward the individual suction openings (4)of the respective monitored areas (R₁, . . . , R₄). Said fresh airthereby displaces the air samples (6) still within the suction pipesystem (3) which are, for example, blown back out into monitored areas(R₁, . . . , R₄) through the respective suction openings (4).

In accordance with the invention, controller (9) is designed such thatit sends a further signal to blowing device (8) after all the airsamples (6) are blown out of the suction pipe system (3) in order toswitch same off. At the same time or immediately thereafter, controller(9) reactivates suction device (5). By so doing, air samples (6)representative of the room air of the individual monitored areas: (R₁, .. . , R₄) are re-extracted from the individual monitored areas (R₁, . .. , R₄) through the suction pipe system (3) and conveyed to sensor (7).Said sensor (7) detects the presence of fire parameters in the extractedair samples (6) after a specific period of time following the restart ofsuction device (5). The time elapsing between the renewed starting ofsuction device (5) and the initial detecting of fire parameters in there-extracted air sample (6) defines the so-called transit time, whichserves as the basis for localizing the seat of the fire.

A processor (10) is provided to evaluate the transit time determined assuch which compares the transit time determined with transit timescalculated theoretically. The theoretically-calculated transit timesstand in direct correlation to the distance of sensor (7) from suctionopenings (4) of the individual monitored areas (R₁, . . . , R₄), sincethey depend on at least one of the following parameters: length of thesuction pipe system (3) between sensor (7) and the suction openings (4)of the respective monitored areas (R₁, . . . , R₄); the effective flowcross-section of the suction pipe system (3) between sensor (7) and thesuction openings (4) of the respective monitored areas (R₁, . . . , R₄);and the flow rate to the air sample (6) within suction pipe system (3).Thus, with knowledge of at least the length of the respective sectionsof the suction pipe system (3) between sensor (7) and the suctionopenings (4) of the respective monitored areas (R₁. . . , R₄) and theflow rate of the air samples (6) through suction pipe system (3), it ispossible-to localize the site of the fire based on the transit time asmeasured.

The preferred embodiment of the present invention further comprises asensor (12) to measure the flow rate of the air samples (6) in thesuction pipe system (3). The measured flow rates are used by processor(10) to evaluate the measured transit times. It is however also possibleto forgo a sensor (12) for measuring flow rate, whereby the flow rate isdetermined on the basis of device parameters such as, for example, theeffective flow cross-section of the suction pipe system (3), suctioncapacity of the suction device (5), cross-sectional shape andcross-section opening to the suction openings (4).

It is also possible for the fire detection device to determine a transittime in a self-learning mode and calculate all respective transit timesfrom same, storing them in a memory-saved table.

FIGS. 2 a and 2 b each show a graphic representation schematicallydepicting the signal emitted by sensor (7) or controller (9) forcontrolling suction device (5) and blowing device (8). The x-axis hererepresents the time while the y-axis represents the signal of sensor (7)or the control signal of controller (10). In the t₀ to t₁ time interval,suction device. (5) is controlled by controller (10) so as to becontinually active; i.e., extracting air samples (6) from the monitoredareas (R₁, . . . , R₄). A dotted line is used to depict this process inFIG. 2 b. At time point t₁, sensor (7) detects the occurrence of a fireparameter in the extracted air samples (6). In response to the signalemitted by sensor (7) at time point t₁, suction device (5) is switchedoff and blowing device (8) simultaneously activated. The blowing-outperiod corresponds to the period from t₁ to t₂, which is a timedependent upon the output of blowing device (8) and on specificparameters of the suction pipe system (3).

After all the air samples (6) within suction pipe system (3) are blownout at time t₂, controller (9) deactivates blowing device (8) andsimultaneously re-activates suction device (5). Sensor (7) is then againfed air samples (6) accordingly. Decisive for localizing the site of thefire is now the transit time Δ t₁ to Δ t₄. Transit time (Δ t₁, . . . Δt₄) corresponds to the period of time from time point t₂, at whichsuction device (5) is re-activated, to time point t₃ to t₆, at whichsensor (7) again detects a fire parameter in the extracted air samples(6). Said transit times (Δ t₁ . . . Δ t₄) are specific to the individualmonitored areas (R₁, . . . , R₄) and serve the subsequent analysis oflocalizing the site of the fire.

1. Method for detecting and localizing a fire and/or the origin of afire in one or more monitored areas comprising the following processsteps: a) extracting air samples in each case representative of the roomair of the respective individual monitored areas from said individualmonitored areas through a common suction pipe system; b) detecting atleast one fire parameter in the air samples suctioned through suctionpipe system with at least one sensor for detecting fire parameters; c)blowing out the extracted air samples within suction pipe system * bymeans of a blower or suctioning/blower device; d) re-extracting airsamples from the individual monitored areas through suction pipe systemat least until the at least one sensor re-detects a fire parameter inair samples; e) evaluating the time elapsed before the re-detecting ofthe fire parameter in the re-extracted air samples from process step d)in order to localize a fire or the site of an imminent fire in one ofthe plurality of monitored areas; and f) emitting a signal indicatingthe development and/or presence of a fire in one or more of monitoredareas wherein the signal contains further information for a preciselocalization of the fire in said one or more monitored areas.
 2. Methodas claimed in claim 1, further comprising the following process stepssubsequent to process step a): a1) determining the flow rate to airsamples in suction pipe system during the continuous extraction ofrespective air samples from individual monitored areas; and a2)calculating the time necessary to fully blow out air samples located insuction pipe system.
 3. Method as claimed in claim 1, wherein processstep c) comprises the process step of determining the flow rate duringsaid blowing out in order to calculate the time necessary to fully blowout the air samples located within suction pipe system.
 4. Method asclaimed in claim 1, further comprising the following process stepssubsequent to process step d): d1) determining the flow rate to airsamples in suction pipe system during the renewed extraction ofrespective air samples from individual monitored areas; and d2)calculating the transit time of respective air samples representative ofthe room air of the individual monitored areas during the renewedextraction of respective air samples from individual monitored areas. 5.Method as claimed in claim 1, wherein the air sampling performed inprocess steps a) and d) is realized by means of a suction device,wherein the subsequent re-extraction of air samples performed in processstep d) ensues with a suction line which is reduced in comparison to thesuction line used in process step a).
 6. Method as claimed in claim 1further including an auto-adjusting procedure comprising the followingprocess steps: i) artificially producing a fire parameter at suctionopening at the most distant monitored area from the at least one sensorover the entire time of the auto-adjusting procedure; ii) suctioning airsamples from individual monitored areas through common suction pipesystem until the at least one sensor detects the artificially-generatedfire parameter in extracted air samples; iii) blowing out extracted airsamples located in suction pipe system by means of a blowing orsuctioning/blowing device; iv) renewed extraction of air samples fromindividual monitored areas through suction pipe system at least untilsensor redetects an artificially-generated fire parameter in airsamples; v) evaluating the transit time elapsed until the re-detectionof the artificially-generated fire parameter in the re-extracted airsamples performed in process step iv) in order to determine the maximumtransit time for the suction pipe system; vi) calculating the transittimes for respective air samples representative of the room air ofindividual monitored areas from individual monitored areas based on themaximum transit times determined in process step v) and theconfiguration of suction pipe system, in particular the distance betweensuction openings, the diameter to the suction pipe system and thediameter to suction openings; and vii) storing the calculated transittimes for respective air samples in a table.
 7. Method claim 6, whereinthe auto-adjusting procedure according to process step vii) furthercomprises the following process step: viii) utilizing a correctingfunction on the calculated transit times stored in the table in order toupdate the transit time values occurring for the individual monitoredareas.
 8. Method as claimed in claim 6, wherein the analysis of thetransit time occurring in the event of a fire is made by comparing theoccurring transit time with the respectively calculated transit timessaved to the table in the auto-adjusting procedure.
 9. Method as claimedin claim 1, wherein the analysis of the transit time occurring is madeby comparing the occurring transit time with the respective transittimes calculated theoretically for individual monitored areas independence on at least one of the following parameters: the length ofthe respective sections of the suction pipe system between the at leastone sensor and the suction openings of the respectively monitored areasdisposed in suction pipe system; the effective flow cross-section ofsuction pipe system and/or the respective sections of suction pipesystem between the at least one sensor e and the respective monitoredareas; and the flow rate of the air samples in suction pipe systemand/or in the respective sections of suction pipe system between the atleast one sensor e and the suction openings of the respective monitoredareas.
 10. Fire detection device for detecting and localizing a fireand/or the origin of a fire in one or more monitored areas comprising asuction pipe system connecting said monitored areas which communicateswith each individual monitored area by means of at least one suctionopening, a suction device for extracting representative air samples(from individual monitored areas by means of suction pipe system andsuction openings, and at least one sensor for detecting at least onefire parameter in the air samples suctioned through suction pipe system,characterized by a blowing device blowing out the air samples suckedinto suction pipe system when the at least one sensor detects at leastone fire parameter in said extracted air samples, and by at least oneindicator element which identifies the site of a fire in one ofmonitored areas and/or by a communication device which transmitsinformation on the development and/or presence of a fire in one or moreof said monitored areas and on the precise location of the fire in saidone or more monitored areas to a location remote of the device. 11.Device as claimed in claim 10, further comprising a controller for atime-coordinated controlling of suction device and blowing device inagreement with a signal emitted by the at least one sensor g when saidat least one sensor detects at least one fire parameter in air samples.12. Device as claimed in claim 10, further comprising a memory means forstoring the transit time values.
 13. Device as claimed in claim 10,further comprising at least one smoke generator arranged near a suctionopening and artificially generating a fire parameter for setting andtesting the fire detection device.
 14. Device as claimed in claim 10,further comprising at least one sensor for measuring the flow rate ofair samples in the suction pipe system.
 15. Device as claimed in claim10, further comprising a processor for evaluating a signal emitted bysensor ( when said at least one sensor ( detects a fire parameter in anair sample ( and a control signal emitted by controller to suctiondevice and/or blowing device.
 16. Device as claimed in claim 10, whereinthe diameters and/or the cross-sectional shape to individual suctionopenings is configured contingent upon respective monitored areas. 17.Device as claimed in claim 10, wherein the diameters and/or thecross-sectional shape to the individual sections of suction pipe systembetween the at least one sensor and the respective monitored areas isconfigured contingent upon the respective monitored areas.
 18. Device asclaimed in claim 10, wherein the suction device and the blowing deviceare configured together as one blower which changes the direction itconveys air in response to a control signal from controller.
 19. Deviceas claimed in claim 18, wherein the blower is a reversing-rotation fan.20. Device as claimed in claim 18, that wherein the blower is a fanhaving ventilation flaps.
 21. Application of the device as claimed inclaim 10 as a fire detection component of a fire extinguishing systemfor activating the introduction of a fire extinguishing agent in one ofmonitored areas.